This morning I saw this situation:
- I had already created a new project
- students signed up for new user accounts, the process of which logged them in to The Combine
- as they signed up, I added them into the project (as Editors)
- they refreshed their browser window and saw an error message, which is partially shown here:
Testing revealed that the new users could not access the project until they had logged out and then logged back in again. This is not entirely intuitive, so detailing here so that others might be aware.